Lithium-ion accumulators are suitable as batteries for hybrid automobiles and electric vehicles because they offer high energy density, are thermally stable and are not subject to memory effect. On the other hand, lithium-ion accumulators are sensitive to mechanical stresses because, mechanical damage can very easily lead to internal short circuits. Lithium-ion accumulators must be protected from mechanical stresses when installed in a vehicle.
A mechanism that protects a battery arranged in the region of the rear luggage compartment is disclosed in EP 1 992 513 A1. In the '513 application, the front region of the battery is located on a cross member arranged rigidly between the two side members of the vehicle. The battery and cross member are connected by screws that pass through slots running in the longitudinal direction of the vehicle. In the event of a collision in which the side members are deflected upwardly, the battery can be displaced relative to the cross member. The rear part of the battery is connected to the side members by pivoted levers that permit relative movement between battery and side member in the event of a collision. Although this known mechanism may provide protection of the battery in rear-end collisions, it offers no protection at all against a side impact.
A cover element for a battery arranged in a luggage compartment is known from US 2001/0030069 A1. However, this cover element serves only to ensure a cooling channel for the battery. This cover element is not provided or designed for load absorption in the event of a crash.
This disclosure is directed to the above problems and other problems as summarized below.